Question: Simplify the following expression: $z = \dfrac{4r + 2}{8r + 10} - \dfrac{8r - 3}{8r + 10}$
Explanation: Since the expressions have the same denominator we simply subtract the numerators: $z = \dfrac{4r + 2 - (8r - 3)}{8r + 10}$ Distribute the negative sign: $z = \dfrac{4r + 2 - 8r + 3}{8r + 10}$ Combine like terms: $z = \dfrac{-4r + 5}{8r + 10}$